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Antimicrobial resistance is a global challenge that impacts both human and veterinary health care. The resilience of microbes is reflected in their ability to adapt and survive in spite of our best efforts to constrain their infectious capabilities. As science advances, many of the mechanisms for microbial survival and resistance element transfer have been identified. During the 2012 meeting of Antimicrobial Agents in Veterinary Medicine (AAVM), experts provided insights on such issues as use vs. resistance, the available tools for supporting appropriate drug use, the importance of meeting the therapeutic needs within the domestic animal health care, and the requirements associated with food safety and food security. This report aims to provide a summary of the presentations and discussions occurring during the 2012 AAVM with the goal of stimulating future discussions and enhancing the opportunity to establish creative and sustainable solutions that will guarantee the availability of an effective therapeutic arsenal for veterinary species.  相似文献   
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Opiates are widely used analgesics in anesthesiology, but they have serious adverse effects such as depression of breathing. This is caused by direct inhibition of rhythm-generating respiratory neurons in the Pre-Boetzinger complex (PBC) of the brainstem. We report that serotonin 4(a) [5-HT4(a)] receptors are strongly expressed in respiratory PBC neurons and that their selective activation protects spontaneous respiratory activity. Treatment of rats with a 5-HT4 receptor-specific agonist overcame fentanyl-induced respiratory depression and reestablished stable respiratory rhythm without loss of fentanyl's analgesic effect. These findings imply the prospect of a fine-tuned recovery from opioid-induced respiratory depression, through adjustment of intracellular adenosine 3',5'-monophosphate levels through the convergent signaling pathways in neurons.  相似文献   
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Two field trials were conducted in a beef cow herd in Saskatchewan to determine the effectiveness of a combined Pasteurella haemolytica and Haemophilus somnus vaccine in increasing passively and actively acquired antibodies in beef calves. Vaccination of dams at 4 and/or 7 weeks prepartum was associated with increased antibody titers to P. haemolytica and H. somnus in their serum (P < 0.05), colostrum (P < 0.05), and serum of their calves at 3 days and 1 month of age (P < 0.05). There was no significant (P > 0.05) difference in antibody titers in the colostrum and serum of calves from single or double vaccinated dams. Calves vaccinated at 1 and 2 months of age in the face of maternal antibodies to P. haemolytica and H. somnus had significantly (P < 0.05) higher antibodies to P. haemolytica and H. somnus at 4 and 6 months of age than did unvaccinated calves. Calves vaccinated at 3 and 4 months of age in the face of low levels of preexisting antibodies had significantly (P < 0.05) higher antibodies to P. haemolytica at 5 months of age and to H. somnus at 5 and 6 months of age than did unvaccinated calves. Calves vaccinated once at 4 months of age had significantly (P < 0.05) higher antibody titers to P. haemolytica and H. somnus at 4.5 months of age than did unvaccinated calves, but this difference was not apparent at 6 months of age.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The first evidence of proliferative kidney disease (PKD) in an Austrian river (the River Kamp) was documented in 2016, and no information on the PKD infection status of trout in other rivers was available. Since then, brown trout (Salmo trutta fario) and rainbow trout (Oncorhynchus mykiss) have been collected from rivers in Upper and Lower Austria for different diagnostic purposes. In this study, we summarize the recent findings of a first survey concerning the distribution of Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD), from these samples. Between September 2015 and October 2017, a total of 280 brown trout and 39 rainbow trout were collected from 21 rivers in the provinces of Upper and Lower Austria. T. bryosalmonae was detected by PCR of kidney tissue in 17 of 21 sampled rivers and in 138 of 280 brown trout as well as in 11 of 39 rainbow trout. Pathological signs of PKD (e.g., hypertrophy of the kidney) were observed in 33 analysed brown trout and six rainbow trout samples. No correlations between fish infected by Tbryosalmonae and the parameters size and age class, condition factor, geological origin of the streams and distribution within the river course were found, while positively tested fish are significantly increased at sampling sites exceeding water temperatures of 15°C for median periods of 115 days. The prevalence within the affected streams or stream sections is highly variable, and in single rivers, infection rates of up to 90% are confirmed.  相似文献   
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Methane emissions from upland forest soils and vegetation   总被引:1,自引:0,他引:1  
Most work on methane (CH(4)) emissions from natural ecosystems has focused on wetlands because they are hotspots of CH(4) production. Less attention has been directed toward upland ecosystems that cover far larger areas, but are assumed to be too dry to emit CH(4). Here we review CH(4) production and emissions in upland ecosystems, with attention to the influence of plant physiology on these processes in forests. Upland ecosystems are normally net sinks for atmospheric CH(4) because rates of CH(4) consumption exceed CH(4) production. Production of CH(4) in upland soils occurs in microsites and may be common in upland forest soils. Some forests switch from being CH(4) sinks to CH(4) sources depending on soil water content. Plant physiology influences CH(4) cycling by modifying the availability of electron donors and acceptors in forest soils. Plants are the ultimate source of organic carbon (electron donor) that microbes process into CH(4). The availability of O(2) (electron acceptor) is sensitive to changes in soil water content, and therefore, to transpiration rates. Recently, abiotic production of CH(4) from aerobic plant tissue was proposed, but has not yet been verified with independent data. If confirmed, this new source is likely to be a minor term in the global CH(4) budget, but important to quantify for purposes of greenhouse gas accounting. A variety of observations suggest that our understanding of CH(4) sources in upland systems is incomplete, particularly in tropical forests which are stronger sources then expected.  相似文献   
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全反射X-射线荧光法分析茶叶中的矿质元素   总被引:6,自引:0,他引:6  
用全反射X -射线荧光法 (TXRF)分析了江西婺绿和宁红茶的矿质元素含量。结果表明 ,所测茶叶中P、S、K、Ca的含量在 2 4 70~ 30 70 0 μg/g ;Mn、Fe在 2 0 6~ 10 70 μg/g ;Ti、Ni、Cu、Zn、Rb、Sr、Ba在 5 5~ 12 2 μg/g ;Pb含量均小于 4 0 μg/g (干基 )。宁红还表现出 ,品质越好 ,P、Ni、Zn含量越高 ,而K、Ca、Mn、Sr、Ba含量则相反。茶汤中K、Rb、Ni的浸出率为 30 5%~ 86 4% ;P、S、Mn、Cu、Zn、Sr为 11 6 %~ 4 2 4% ;Ca为 7 2 %~ 12 6 % ;Fe为 1 1% -2 6 %。茶汤中Ti、Ba、Pb的含量均低于TXRF法的检测限。宁红茶汤还表现出 ,品质越好 ,K、Ca、Mn、Zn、Rb、Sr的浸出率越高。但红茶汤中的K、Zn、Rb、Ni浸出率明显低于绿茶  相似文献   
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Zusammenfassung Mit Hilfe eines einfachen Tüpfeltests auf cholinesterasehemmende Substanzen ist es möglich, die Ergebnisse des routinemäßig durchgeführten Insektizid-Screenings zu ergänzen. Der Test wird beschrieben und die ersten Ergebnisse an 75 Phenyl-N-methyl-carbamaten werden in tabellarischer Form dargestellt. Cholinesterasehemmung und insektizide Wirkung korrelieren miteinander. Struktur-Aktivitäts-Beziehungen werden ebenfalls kurz skizziert.
Summary A simple spot test for cholinesterase inhibiting substances may be a valuable addition to the routine screening procedure of certain insecticides. The new spot test is described in detail and the results obtained with 75 phenyl-N-methylcarbamates are described. A relationship was found between insecticidal activity and cholinesterase inhibition and certain conclusions concerning biological activity and insecticide-structure may be drawn from the results.
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